Induction of immunocontraceptive effects in both male and female mice immunized with GnRH vaccine

Background Gonadotropin‐releasing hormone (GnRH) plays a pivotal role in regulating the reproductive endocrine system. Objective An immunocontraception vaccine aimed at inhibiting the functions of GnRH is tested as a potential tool for controlling animal populations. Methods We developed a recombinant immunocontraceptive vaccine composed of GnRH‐I and GnRH‐II (GnRH I+II), which was conjugated with Salmonella typhimurium flagellin. Forty‐eight BALB/c mice aged 4 weeks were divided into four groups (each group had n = 12): non‐vaccinated male (NVM), non‐vaccinated female (NVF), vaccinated male (VM), and vaccinated female (VF). Mice in the vaccinated groups were vaccinated twice by intramuscular injection at 0 and 2 weeks with 300 μg of the recombinant GnRH protein complex per mouse. Mice in the non‐vaccinated groups were injected with saline and served as the unimmunized controls. Twenty‐four pairs of male and female mice were mated for 10–12 weeks after initial immunization in four groups: 6 NVF × 6 NVM, 6 VF × 6 NVM, 6 NVF × 6 VM, and 6 VF × 6 VM. Results: An increase (p
We developed a new form of immunocontraceptive vaccine composed of GnRH‐I and ‐II complex conjugated with STF‐2. We provide the vaccine efficacies with higher anti‐GnRH antibodies in mice. The vaccine containing the GnRH‐I + II peptide linked to STF‐2 induced the suppression of fertility by inhibiting testicular and ovarian functions and reducing sex hormone levels in both male and female mice. In addition, the effects of fertility reduction were confirmed through mating experiments .